code: def suppress_unsupported_keys(metadata, unsupported_keys=None):
      # assert isinstance(unsupported_keys, set)
      if isinstance(unsupported_keys, set):
          for key in metadata:
              if not is_valid_metadata_key(key):
                  unsupported_keys.add(key)
      return {
          key: value
          for key, value in metadata.items()
          if is_valid_metadata_key(key)
      }
  
file_path: jupytext/src/jupytext/metadata_filter.py
imports: from copy import copy
  from .cell_metadata import _JUPYTEXT_CELL_METADATA, is_valid_metadata_key
label_desc: Use image node_id 6 for calling a global function with example usage: suppress_unsupported_keys(metadata, unsupported_keys) and returns: unknown